Dental positioning device



Jan. 4, 1966 R. sPALTEN DENTAL POSITIONING DEVICE Filed Dec. 21, 1962 INVENTOR. Raaf/ar Shui-W United States Patent O 3,226,828 DENTAL POSITIGNING DEVICE Robert Spalten, 333 Central Park W., New York, N.Y. Filed Dec. 21, 1962, ser. No. 246,614 5 Claims. (Cl. 32-67) This invention relates to a device for positioning dental tools, and more particularly to such a device useful for positioning a dental tool for the preparation of parallel holes in, or parallel surfaces on, teeth or models of the teeth.

In constructing fixed bridgework, as well as in many other dental operations, it is often necessary to drill parallel holes in or grind parallel surfaces on the occlusal or axial surfaces of the patients teeth. While the dentist may perform such operations without the use of external positioning or guiding mechanisms, in such instances he must exercise dexterity and judgment to produce the requisite uniform and precise results. Various positioning devices have therefore been devised to assist the dentist in performing such parallel drilling or grinding operations.

One type of positioning device previously suggested for dental hand pieces includes iixed guides which are wall or floor mounted; while such a device insures vertical motion of the dental tools, it does not compensate for the inevitable slight angular movements of the patients jaw during the operation, and thus has not proved satisfactory for this purpose.

More recently it has been proposed to provide a paralleling device including a positioning member disposed within the patients mouth which swivelly supports a mechanical linkage connected to the dental handpiece. The linkage and hand piece pivot about a fixed reference direction determined by the positioning member and may be displaced laterally of a desired operating direction, in which direction it is desired to act upon each of the patients teeth. While this device permits drilling of closely spaced teeth at approximately the same angular orientation, it has not been found entirely satisfactory since, in addition to its relative complexity and difiiculty to manipulate, the dental hand piece thereof must, in order to operate on more widely spaced apart teeth, describe a conical surface of revolution relative to the fixed reference direction and thus be oriented at varying angles with respect to the several` teeth to be operated upon.

It is accordingly among the objects of the present invention to provide a device useful -for positioning a dental tool in accurate parallel alignment with respect to each of the teeth to be operated upon, to thereby facilitate parallel drilling, grinding or like operations on each of such teeth.

An additional object of the invention is to provide such a device which is relatively simple and economical to manufacture and use. Y

A yet further object is to provide such a device which may be readily disassembled and reassembled for re-use on the same patient during a subsequent visit and which may also be utilized for other patients in the-interim period, without reducing the accuracy and precision of its operation.

Other objects and advantages of the invention will become more apparent hereinafter.

I have devised a positioning device useful for preparing parallel |holes and surfaces in teeth or `for performing other parallel dental operations, which includes a holder for supporting a dental tool in alignment with a predetermined operating axis relative to the teeth to be operated upon, `a parallelogram linkage connected to the holder supporting the same, and a mounting member adapted to be supported by the axial and occlusal surfaces of the teeth on one side of the mouth and supporting the r. ice

parallelogram linkage in turn. A joint is provided for supporting the parallelogram linkage relative to the mounting member with two or more parallel members of the linkage aligned with the predetermined operating axis. Using this device the dentist, upon choosing any desired operating axis, positions the parallelogram linkage supported by the mounting member in alignment with the operating axis, as described more fully hereinafter, and proceeds to operate on the several teeth on the portion of the mouth not supporting the mounting member.

rPhe positioning device of the invention is extremely accurate, the parallelogram linkage facilitating displacement of the dental tool between teeth while maintaining the operating angle of the tool in alignment with the predetermined operating axis. Moreover, the device utilizes `pivotally movable elements which may be readily manipulated Without any particular degree of mechanical dexterity and may be utilized by the dentist without interference with his finger grasp or impairment of his visibility of the field of operation. Nevertheless, the positioning device is relatively simple and may be cheaply and eiiiciently produced.

It has additionally been found that the component elements of the positioning device of the invention may readily be disassembled at the conclusion of a patients visit, the mounting member thereof being retained for subsequent treatment of the same patient and the rest of the device -being separated therefrom and used to facilitate parallel dental operations upon different patients. Also, the device may be utilized in connection with a model of the patients jaw structure, particular desired operating axes being determined from the model and thereafter transferred to the patients mouth, in accordance with an overall planning procedure.

The positioning device may also be readily adapted for parallel dental operations on either the occlusal or axial surfaces of teeth, as will become readily apparent hereinafter.

For a fuller understanding of the invention, reference is now made to the following detailed description of preferred embodiments of the positioning device, taken in connection with the accompanying drawing in which:

FIGURE l is a perspective View illustrating one embodiment of the dental positioning device of the present invention;

FIGURE 2 is a View similar to FIGURE l showing a further embodiment of the invention, for determining an appropriate operating axis in conjunction with a model of the lower jaw and teeth of a patient;

FIGURE 2A is a sectional view, enlarged relative to FIGURE 2, showing the joint member illustrated in FIG- URE 2;

FIGURES 3 and 4 are sections through alternative forms of the mounting member of the positioning device, including two further embodiments of joint constructions for supporting the parallelogram linkage on the mounting member; and

FIGURE 5 is a fragmentary perspective view showing a further embodiment of the positioning device, with the parallelogram linkage thereof not shown, for purposes of clarity, which embodiment is designed to facilitate parallel dental operations with repsect to the labial surfaces of the anterior teeth.

Refering initially to FIGURE l, the embodiment of the positioning device illustrated is supported by the axial and occlusal surfaces of the lower bicuspids and molars on the right side 11 of a mouth. As shown, the positioning device supports a schematically represented dental hand piece 13 having a burr or diamond stone 14 to be used for drilling holes in the occlusal surfaces 15 of the lower bicuspids and molars on the side 12 of the mouth not supporting the positioning device.

The device is adapted to locate the burr 14 for drilling parallel holes in the surfaces aligned with any predetermined operating axis, such as that shown at 16 in FIGURE 1. The operating axis, it will be understood, may be chosen by the dentist in accordance with the problems presented by the particular case; the instant device thereafter facilitates forming parallel holes in the several teeth in accurate and precise alignment.

The positioning device includes a holder for the hand piece 13, which may comprise a locking tube 17 formed in the hand piece, extending therethrough parallel to the burr 14, and an engaging end element 20 of a parallelogram linkage, indicated generally at 18, connected to the holder. The end element 20 may be bifurcated and biased outwardly at its extremity, and provided with an intermediate shoulder to prevent accidental slippage or disengagement from the locking tube during use.

The parallelogram linkage includes a rst or operating rod 19 adapted to be received in and removably engaged by the locking tube 17, a second or positioning rod 21 and a parallelogram frame constituting a pair of transverse links 22 pivotally connected at their ends to U- shaped members mounted on a pair of support tubes 23. Swivelly attached within the respective tubes 23 are the operating and the positioning rod 21; the end elements of such rods may be bifurcated in the manner described above to facilitate engagement within the tubes 23. Such rods include portions 24 and 25, respectively, extending parallel to the operating axis 16 through the burr 14.

The parallelogram linkage 18 facilitates transverse and axial displacement of the hand piece 13 while maintaining the burr 14 thereof aligned with the operating axis. While the operating axis has been indicated in the vertical direction in the drawing it will be understood that such axis, as well as the portion 24 of the operating rod 19 and portion 25 of the positioning rod 21 of the linking structure 18, may be disposed at other angles in accordance with the dentists desires.

A mounting member 26 is provided for supporting the parallelogram linkage 18 of the positioning device and the hand piece 13 secured thereto. The mounting member is adapted to be supported by the axial and occlusal surfaces of the teeth on the one side 11 of the lower jaw as illustrated in FIGURE l. Such member includes an impression tray 27 dening a channel in which the teeth are received; the channel contains a layer 28 of a plastic material which hardens at ordinary room temperatures to conform to the jaw structure upon which the mounting member 26 is supported.

The mounting member may be retained within the patients mouth by manually maintaining the impression tray 27 in contact with the lower jaw. While the opposing teeth are not required to support the mounting member, if desired, a rubber block (not shown) may be interposed between the impression tray 27 and the opposing teeth.

A joint 29 is provided on the outer end of the mounting member 26 for removably receiving and supporting the positioning rod 21 of the parallelogram linkage 18. In the simple form illustrated in FIGURE 1, the joint 29 includes a bearing sleeve 31 supported within an aperture provided in the mounting member; the bearing sleeve is relatively loosely mounted prior to use and may be retained within the aperture by means of upper and lower collar elements, one of which is indicated at 32. The positioning rod 21 of the parallelogram linkage received in the bearing sleeve 31 may be aligned with the operating axis by aligning the sleeve with such axis and xing the desired alignment by coating the abutting surfaces of the bearing sleeve and the mounting member 26 with a hardenable layer 33 of a suitable plastic material.

In use, the plastic layer on the mounting member 26, which may comprise modeling compound or any of the well-known room temperature setting thermoplastic materials used in the dental eld, is initially softened by heat- CII ing and is then placed over the patients teeth. Indentations are thereby formed in the thermoplastic material 28, which conform to the configuration of the teeth on the side 11 of the lower jaw. The location of the mounting member 26 in the mouth is thus determined so that it can be removed, separated from the other components of the positioning device, and the device subsequently reassembled without changing the position of such member, to facilitate interrupting the dental operation whenever desired and resuming at a future visit.

In order to drill parallel holes in two or more teeth on the opposite side 12 of the mouth after locating the mounting member 26, the hand piece 13 is displaced laterally of the mouth and moved to the occlusal surface of each successive tooth. At the same time the links 22 of the parallelogram linkage secured to the hand piece pivot relative to the positioning rod 21, and the positioning rod pivots within the bearing sleeve 31 to accommodate the motion of the hand piece, the burr 14 being maintained throughout disposed longitudinally of and in alignment with the operating axis 16. Since the elements of the parallelogram linkage are aligned with the operating axis and are in no way dependent upon movement of the mounting member 26 relative to the patients jaw, the burr 14 or other dental tool is maintained precisely parallel to the operating axis, irrespective of the distance between the individual teeth operated upon.

A further embodiment of the positioning device is shown in FIGURE 2, illustrating its operation in connection with a model 41 of the lower jaw of a patient. As shown in the drawing, the positioning device includes a holder ring 42 mounted on a hand piece 13. The ring 42 has a mounting tube secured thereto transversely of the hand piece for receiving the end of an operating rod 19a. The operating rod may be fixed against accidental slippage relative to the mounting tube in which it is received, in the manner described above in connection with FIGURE 1. The holder ring 42 and associated elements are utilized to adapt existing dental hand pieces for use with the operating device of the invention.

The parallelogram linkage 18a shown in FIGURE 2 includes an operating rod 19a and a positioning rod 21a having portions 24a and 25a, respectively, extending longitudinally of the operating axis 16a. The rods 19a and 21a are pivotally connected to the ends of a parallelogram frame 43, whose elements are pivotally mounted relative to one another.

The portion 25a of the positioning rod 21a is received in and supported by a joint 29a mounted on a mounting bracket 44 secured to the jaw model 41. The joint 29a (see FIGURE 2A) comprises a housing 45 supported by the mounting bracket 44 and having therein a pivotally mounted ball assembly 46. An internal sleeve 47 of the ball assembly engages the portion 25a of the positioning rod 21a and is adapted to be locked in any desired angular configuration aligned with a predetermined operating axis 16a, by means of a thumb screw 48 or similar device.

Further forms of joints which may be supported on the mounting bracket 44 or, as illustrated, on the mounting member 26 of the positioning device, are shown in FIGURES 3 and 4. The joint of FIGURE 3 includes a vertically offset leaf spring 49, the leaves of which are dimpled to dene a socket 51 for the ball assembly 46. The sleeve 47 of the ball assembly and the positioning rod received therein are locked in alignment with the operating axis by means of a wing nut 52 mounted on a bolt 53 for stressing the leaves of spring 49 toward one another.

The joint of FIGURE 4 includes a modified ball assembly `46a received in a socket 54 formed on an extension of the mounting member 26. The sleeve 47a which receives the positioning rod is threaded at one end for receiving a wing nut 52; upon tightening the wing nut the sleeve is xed in any desired angular position.

andf 4 are formed on extensions which are vertically offset from the 'mounting mem-bers to which they are secured. In this manner the ball assemblies of such joints are placed approximately midway between the upper and lower jaws to -permit efficient use of the positioning device for dental loperations on either the upper or lower teeth.

"A further embodiment of the positioning device, adapted` to facilitate parallel dental `Operations on the axial surfaces of the teeth other than those upon which the mounting member is supported,` is shown in fragment in FIGURE 5. The device includesa straight hand piece 55 illustrated in anterior teeth 56 longitudinally of an operating axis 16b. The hand piece is secured by a holder ring 42ra and an integral mounting tube 57 extending longitudinally of the hand piece, to the operating rod 19b of `a parallelogram linkage which may, for example, be of the same structure as either of linkages 18 or 18a described above.

The ,positioning rod 21b of the linkage is supported longitudinally of the operating axis by a modified joint 29b, which is similar to the jointillustrated in FIGURE 3, except that the ball assembly 4-6 is mounted in a socket definedat one end of a spring urged alligator clip 57 mounted on a flange 58 of a mounting member 26a. It is noted that the ball member of ball assembly 46 is desirably of plastic, e.-g.`, of nylon, to provide a smoothly functioning joint member.

When it is desired to tightly grip'the ball assembly 46 in order to tix the orientation 'of the positioning rod 2lb (and hence the operating rod 19h and the straight hand piece 55) to maintainit in alignment with the desired operating axis, a thumb screw 59 is tightened, thereby increasing the clip pressure on the ball assembly.

It will be understood that the individual elements of the embodiments of the positioning device shown in the several figures, viz., the holder for supporting the dental tool, the parallelogram linkage connected to the holder, the mounting member for locating the device relative to the jaw to be operated on, or the -joint for supporting the parallelogram linkage relative to the mounting member, may be interchanged as desired. In any case, a positioning device is provided which facilitates effecting precise parallel dental operations on the occlusal or axial surfaces of `teeth, the parallelogram linkage of which is readily separable from both the mounting member and the dental tool to permit efiicient disassem-bly and re-use of the parts of the device as desired.

The positioning device of the invention may be utilized as anintegral part of a systematic dental procedure for constructing fixed bridge work or otherwise correcting general existing dental problems. In such a procedure the dentist may initially make a model of the patients mouth corresponding to the model shown in FIGURE 2 hereof. Employing the model he may then plan the operating angle at which he wishes to drill or otherwise operate on the patients teeth, fixing the joint 29a supported on the mounting member 44 in alignment with such angle. The impression tray 27 of mounting member 26, possessing the impression of the teeth on side 11 of the patients jaw, may then, for example, be placed on the corresponding jaw section 11a of the model. The joint 29 on mounting member 26 is then positioned at the desired operating angle by placing a parallel linkage, e.g., linkages 18, 18a or a simplied linkage including a pair of parallel leg members pivotally joined by a suitable link or links, between the joint 29a and the joint 29. After fixing the operating angle, e.g., by hardening the thermoplastic coating 33 about the bearing sleeve 31 and the abutting surfaces of the mounting member 26, the mounting member may be replaced in the patients mouth with the desired operating angle established. The dentist may then readily manipulate the positioning device to drill the patients teeth at the preselected operating angle.

While, inthe preceding specifi-cation, the preparation of parallel holes in teeth in the center and left-hand side of the lower jaw, utilizing a positioning device supported on the axial and occlusal surfaces lof teeth on the righthand side of the lower jaw has been specifically described,

. it will be understood that the positioning device of the present invention may be utilized to support dental tools for parallel operations on either side of either the upper or lower jaws, supported by a member mounted on the axial and occlusal surfaces of the teeth on the corre- Vsponding opposite side of the mouth. Moreover, it is intended that the positioning device of the present invention may also be used in connection with suitable dental tools for grinding parallel sur-faces or otherwise performling parallel operations on teeth;

It Will also be appreciated that the positioning device of my invention may be utilized to facilitate parallel operations on laboratory models of teeth as well as to simplify parallel positioning of dental tools for direct operation upon patients.

Since these and other changes may be made in the dental positioning device of this invention without departing from the scope thereof, it is intended that all matter contained in the above description shall be linterpreted as illustrative-and not in a limiting sense.

What is claimed is:

1. A positioning device useful for preparing parallel holes in and surfaces on teeth, comprising:

i (a) a mounting member a-dapted to be supported by the laxial and occlusal surfaces of the teeth on oneI side Iof a jaw, said member including a first portion defining the location of said mounting member and a second, extension portion;

(b) joint means supported by the extension portion of the mounting member, said means including a bearing element f-or receiving the positioning rod of the parallelogram linkage defined hereinafter and gripping means for rigidly fixing said element in alignment with any predetermined operating axis;

(c) a parallelogram linkage secured to said joint means and being displaced from said mounting member, said linkage including:

(l) a positioning rod pivotally supported by the joint means and having at least a portion thereof extending in alignment With said operating axis;

(2) a transverse linkage pivotally secured to said positioning rod, and

(3) an operating rod pivotally secured to said transverse linkage and having at least a portion thereof extending parallel to said operating axis; and

(d) a holder for supporting a dental tool aligned with said predetermined operating axis at a point spaced from the operative end of the tool, the holder being secured to said operating rod in order that the dental tool supported thereby may operate on a plurality of teeth on the portion of the jaw not supporting the mounting member.

2. A positioning device useful for preparing parallel holes in and surfaces on the axial and occlusal surfaces of teeth, comprising:

(a) a mounting member adapted to be supported by the axial and occlusal surfaces of the teeth on one side of a jaw, said mounting member including a first portion defining an impression tray having a layer of plastic material secured therein to be placed over said teeth for receiving an impression thereof and thereby defining the location of said mounting member, and a second extension portion;

(b) joint means supported by the extension portion of the mounting member, said means including a bearing sleeve for receiving the positioning rod of the parallelogram linkage defined hereinafter and gripping means for rigidly fixing said sleeve in alignment with any predetermined operating axis;

(c) a parallelogram linkage secured to said joint means and being displaced from said mounting member, said linkage including:

(1) a positioning rod pivotally supported by the joint means and having at least a portion thereof extending in alignment with said operating axis,

(2) a transverse linkage pivotally secured to said positioning rod, and

(3) an operating rod pivotally secured to said transverse linkage and having at least a portion thereof extending parallel to said operating axis; and

(d) a holder for supporting a dental tool aligned with said predetermined operating axis, at a point spaced from the operative end of the tool, the holder being secured to said operating rod, in order that the dental tool supported thereby may operate on a plurality `of teeth on the portion of the jaw not supporting the mounting member.

3. The positioning device defined in claim 2 in which said bearing sleeve is received in an aperture in said mounting member and said gripping means for rigidly fixing the sleeve in alignment with any predetermined operating axis comprises a thermoplastic coating covering at least a portion of said bearing sleeve and the adjacent surfaces of said mounting member, which coating is hardened under ordinary ambient conditions.

4. The positioning device defined in claim 2, in which said joint means includes a ball assembly having an aperture therethrough containing said bearing sleeve, a socket means associated with said mounting member and pivotally supporting said ball assembly, and a clamping means for fixing said ball assembly in position with the bearing sleeve in desired alignment.

5. The parallel positioning device defined in claim 2, in which said holder comprises a bracket member adapted to be secured to the dental tool, said bracket member having a tube for removably receiving one end of said operating rod.

References Cited by the Examiner UNITED STATES PATENTS 1,387,329 8/1921 Stark 32-67 2,318,403 5/ 1943 Karlstrom 32-67 2,434,320 1/1948 Karlstrom 32-67 2,621,408 12/1952 Klein 32-67 2,967,433 1/ 1961 Phillips 74-16 3,063,149 11/1962 Suga 32-67 3,078,580 2/1963 Galuez 32-67 3,083,462 4/1963 Iermyn 32-25 FOREIGN PATENTS 409,985 2/ 1925 Germany. 512,181 8/ 1939 Great Britain.

RICHARD A. GAUDET, Primary Examiner.

JAMES W. HINEY, IR., Assistant Examiner. 

1. A POSITIONING DEVICE USEFUL FOR PREPARING PARALLEL HOLES IN SAID SURFACES ON TEETH, COMPRISING: (A) A MOUNTING MEMBER ADAPTED TO BE SUPPORTED BY THE AXIAL AND OCCLUSAL SURFACES OF THE TEETH ON ONE SIDE OF A JAW, SAID MEMBER INCLUDING A FIRST PORTION DEFINING THE LOCATION OF SAID MOUNTING MEMBER AND A SECOND, EXTENSION PORTION; (B) JOINT MEANS SUPPORTED BY THE EXTENSION PORTION OF THE MOUNTING MEMBER, SAID MEANS INCLUDING A BEARING ELEMENT FOR RECEIVING THE POSITIONING ROD OF THE PARALLELOGRAM LINKAGE DEFINED HEREINAFTER AND GRIPPING MEANS FOR RIGIDLY FIXING SAID ELEMENT IN ALIGNMENT WITH ANY PREDETERMINED OPERATING AXIS; (C) A PARALLELOGRAM LINKAGE SECURED TO SAID JOINT MEANS AND BEING DISPLACED FROM SAID MOUNTING MEMBER, SAID LINKAGE INCLUDING: (1) A POSITIONING ROD PIVOTALLY SUPPORTED BY THE JOINT MEANS AND HAVING AT LEAST A PORTION THEREOF EXTENDING IN ALIGNMENT WITH SAID OPERATING AXIS; (2) A TRANSVERSE LINKAGE PIVOTALLY SECURED TO SAID POSITIONING ROD, AND (3) AN OPERATING ROD PIVOTALLY SECURED TO SAID TRANSVERSE LINKAGE AND HAVING AT LEAST A PORTION THEREOF EXTENDING PARALLEL TO AID OPERATING AXIS; AND (D) A HOLDER FOR SUPPORTING A DENTAL TOOL ALIGNED WITH SAID PREDETERMINED OPERATING AXIS AT A POINT SPACED FROM THE OPERATIVE END OF THE TOOL, THE HOLDER BEING SECURED TO SAID OPERATING ROD IN ORDER THAT THE DENTAL TOOL SUPPORTED THEREBY MAY OPERATE ON A PLURALITY OF TEETH ON THE PORTION OF THE JAW NOT SUPPORTING THE MOUNTING MEMBER. 